nginx: fix CVE-2026-42946

These patches apply the upstream fix sequence as
referenced in [3], using the commits shown in [1] and [2].

[1] https://github.com/nginx/nginx/commit/baef7fdac28e4e1fe26509b50b8d15603393e28e
[2] https://github.com/nginx/nginx/commit/39d7d0ba0799fcff6baee52b6525f45739593cfd
[3] https://nginx.org/en/security_advisories.html

Signed-off-by: Hetvi Thakar <hthakar@cisco.com>
Signed-off-by: Anuj Mittal <anuj.mittal@oss.qualcomm.com>

meta-webserver/recipes-httpd/nginx/files/CVE-2026-42946_p1.patch

@@ -0,0 +1,47 @@
+From baef7fdac28e4e1fe26509b50b8d15603393e28e Mon Sep 17 00:00:00 2001
+From: Sergey Kandaurov <pluknet@nginx.com>
+Date: Wed, 29 Apr 2026 21:56:51 +0400
+Subject: [PATCH] Upstream: reset parsing state after invalid status line
+
+Previously, it was possible to start parsing headers with a wrong
+parsing state after status line was not recognized, as a fallback
+used in the scgi and uwsgi modules.
+
+Reported by Leo Lin.
+
+CVE: CVE-2026-42946
+Upstream-Status: Backport [https://github.com/nginx/nginx/commit/baef7fdac28e4e1fe26509b50b8d15603393e28e]
+
+(cherry picked from commit baef7fdac28e4e1fe26509b50b8d15603393e28e)
+Signed-off-by: Hetvi Thakar <hthakar@cisco.com>
+---
+ src/http/modules/ngx_http_scgi_module.c  | 1 +
+ src/http/modules/ngx_http_uwsgi_module.c | 1 +
+ 2 files changed, 2 insertions(+)
+
+diff --git a/src/http/modules/ngx_http_scgi_module.c b/src/http/modules/ngx_http_scgi_module.c
+index 49977b07b..038380798 100644
+--- a/src/http/modules/ngx_http_scgi_module.c
++++ b/src/http/modules/ngx_http_scgi_module.c
+@@ -1029,6 +1029,7 @@ ngx_http_scgi_process_status_line(ngx_http_request_t *r)
+ 
+     if (rc == NGX_ERROR) {
+         u->process_header = ngx_http_scgi_process_header;
++        r->state = 0;
+         return ngx_http_scgi_process_header(r);
+     }
+ 
+diff --git a/src/http/modules/ngx_http_uwsgi_module.c b/src/http/modules/ngx_http_uwsgi_module.c
+index c1d0035cc..05c08b6c4 100644
+--- a/src/http/modules/ngx_http_uwsgi_module.c
++++ b/src/http/modules/ngx_http_uwsgi_module.c
+@@ -1266,6 +1266,7 @@ ngx_http_uwsgi_process_status_line(ngx_http_request_t *r)
+ 
+     if (rc == NGX_ERROR) {
+         u->process_header = ngx_http_uwsgi_process_header;
++        r->state = 0;
+         return ngx_http_uwsgi_process_header(r);
+     }
+ 
+-- 
+2.35.6

meta-webserver/recipes-httpd/nginx/files/CVE-2026-42946_p2.patch

@@ -0,0 +1,92 @@
+From 39d7d0ba0799fcff6baee52b6525f45739593cfd Mon Sep 17 00:00:00 2001
+From: Sergey Kandaurov <pluknet@nginx.com>
+Date: Wed, 29 Apr 2026 23:02:20 +0400
+Subject: [PATCH] Upstream: fixed parsing of split status lines
+
+If the first response line was split across reads and it didn't appear
+a status line, the portion already processed was lost.  To preserve ABI,
+the change reuses r->header_name_start for proper backtracking on status
+line fallback.
+
+CVE: CVE-2026-42946
+Upstream-Status: Backport [https://github.com/nginx/nginx/commit/39d7d0ba0799fcff6baee52b6525f45739593cfd]
+
+(cherry picked from commit 39d7d0ba0799fcff6baee52b6525f45739593cfd)
+Signed-off-by: Hetvi Thakar <hthakar@cisco.com>
+---
+ src/http/modules/ngx_http_proxy_module.c | 5 +++++
+ src/http/modules/ngx_http_scgi_module.c  | 5 +++++
+ src/http/modules/ngx_http_uwsgi_module.c | 5 +++++
+ 3 files changed, 15 insertions(+)
+
+diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
+index 0778ec728..454ef6270 100644
+--- a/src/http/modules/ngx_http_proxy_module.c
++++ b/src/http/modules/ngx_http_proxy_module.c
+@@ -1835,6 +1835,10 @@ ngx_http_proxy_process_status_line(ngx_http_request_t *r)
+ 
+     u = r->upstream;
+ 
++    if (r->state == 0) {
++        r->header_name_start = u->buffer.pos;
++    }
++
+     rc = ngx_http_parse_status_line(r, &u->buffer, &ctx->status);
+ 
+     if (rc == NGX_AGAIN) {
+@@ -1842,6 +1846,7 @@ ngx_http_proxy_process_status_line(ngx_http_request_t *r)
+     }
+ 
+     if (rc == NGX_ERROR) {
++        u->buffer.pos = r->header_name_start;
+ 
+ #if (NGX_HTTP_CACHE)
+ 
+diff --git a/src/http/modules/ngx_http_scgi_module.c b/src/http/modules/ngx_http_scgi_module.c
+index 038380798..7477df317 100644
+--- a/src/http/modules/ngx_http_scgi_module.c
++++ b/src/http/modules/ngx_http_scgi_module.c
+@@ -1021,6 +1021,10 @@ ngx_http_scgi_process_status_line(ngx_http_request_t *r)
+ 
+     u = r->upstream;
+ 
++    if (r->state == 0) {
++        r->header_name_start = u->buffer.pos;
++    }
++
+     rc = ngx_http_parse_status_line(r, &u->buffer, status);
+ 
+     if (rc == NGX_AGAIN) {
+@@ -1029,6 +1033,7 @@ ngx_http_scgi_process_status_line(ngx_http_request_t *r)
+ 
+     if (rc == NGX_ERROR) {
+         u->process_header = ngx_http_scgi_process_header;
++        u->buffer.pos = r->header_name_start;
+         r->state = 0;
+         return ngx_http_scgi_process_header(r);
+     }
+diff --git a/src/http/modules/ngx_http_uwsgi_module.c b/src/http/modules/ngx_http_uwsgi_module.c
+index 05c08b6c4..d012f4fd4 100644
+--- a/src/http/modules/ngx_http_uwsgi_module.c
++++ b/src/http/modules/ngx_http_uwsgi_module.c
+@@ -1258,6 +1258,10 @@ ngx_http_uwsgi_process_status_line(ngx_http_request_t *r)
+ 
+     u = r->upstream;
+ 
++    if (r->state == 0) {
++        r->header_name_start = u->buffer.pos;
++    }
++
+     rc = ngx_http_parse_status_line(r, &u->buffer, status);
+ 
+     if (rc == NGX_AGAIN) {
+@@ -1266,6 +1270,7 @@ ngx_http_uwsgi_process_status_line(ngx_http_request_t *r)
+ 
+     if (rc == NGX_ERROR) {
+         u->process_header = ngx_http_uwsgi_process_header;
++        u->buffer.pos = r->header_name_start;
+         r->state = 0;
+         return ngx_http_uwsgi_process_header(r);
+     }
+-- 
+2.35.6

meta-webserver/recipes-httpd/nginx/nginx_1.28.3.bb

@@ -3,6 +3,8 @@ require nginx.inc
 SRC_URI:append = " \
     file://CVE-2026-40701.patch \
     file://CVE-2026-42934.patch \
+    file://CVE-2026-42946_p1.patch \
+    file://CVE-2026-42946_p2.patch \
 "
 
 LIC_FILES_CHKSUM = "file://LICENSE;md5=3dc49537b08b14c8b66ad247bb4c4593"

meta-webserver/recipes-httpd/nginx/nginx_1.29.7.bb

@@ -3,6 +3,8 @@ require nginx.inc
 SRC_URI:append = " \
     file://CVE-2026-40701.patch \
     file://CVE-2026-42934.patch \
+    file://CVE-2026-42946_p1.patch \
+    file://CVE-2026-42946_p2.patch \
 "
 
 # 1.28.x branch is the current stable branch, the recommended default